Scientists from the US have created a polymer material that can change shape over time at a pre-set program. In the future, the developers hope this material will be used to create a new generation of medical implants. In the meantime, its scientists have demonstrated the possibility of using artificial flowers.

Flower was created by graduate student Qiaoxi Lee (Qiaoxi Li). Its diameter is several centimeters. Within two minutes, first disclosed the outer red petals, then medium purple, orange and then internal. “I was very surprised when I first saw a flower. It looks quite real, – said professor of polymer chemistry Sergey cervix, who led the study. – It’s a dead piece of material. If you remove the paint, it’s just a white polymer. As if we introduced in the material life. ”

Polymer petals bloom at predetermined time points. Subsequently, according to Sergei neck so will take the desired shape implants introduced into the patient in minimally invasive surgery. The basis material – a polymer gel, which has a density of human cartilage. Sheet form is regulated by two different types of chemical bond. In it there is a small amount of strong covalent bonds and a much larger part of the weaker hydrogen bonds. When the sheet is bent, elastic energy is stored in the strong coupling. Weak links act as opposing forces, they slow unfolding of the material. By controlling the amount, strength and location of the two types of links can create complex structures that are pre-cracking in the programmed sequence.

In an article published in the journal Nature Communications, Sergey Shejko team describes how they have created objects that change shape in a matter of minutes or hours. Unlike other material capable of changing the shape, the polymer gel can do it at the scheduled time without requiring an external trigger pulse, for example, heat or light radiation